This study aims to explore the potential of pollen rain analysis as a method for assessing plant diversity across three bioclimatic zones in northeastern Algeria. The primary objective is to investigate how climate, vegetation structure, and biodiversity are interrelated, particularly how airborne pollen can be used to reveal the composition of plant communities and to evaluate the influence of climatic factors such as humidity and aridity, along with human activities. The research was carried out in three distinct bioclimatic regions of northeastern Algeria, each characterized by unique environmental conditions. The humid zone, located in the Edough Mountains near Annaba, features high rainfall and supports dense, diverse forest vegetation. The sub-humid zone, situated near Souk Ahras, represents a moderately moist forest environment with a mix of plant species. In contrast, the semi-arid zone, found south of Souk Ahras, is defined by low rainfall, higher temperatures, and sparse vegetation adapted to arid conditions. Pollen samples were collected from six strategically selected sites using pollen traps. After collection, the samples were examined under a microscope for identification and counting of pollen grains, allowing for the assessment of plant taxa diversity and relative abundance. Principal Component Analysis (PCA) was then used to identify patterns and relationships among pollen taxa, vegetation types, and environmental variables, with particular attention to indicator species that reflect specific climatic conditions and anthropogenic influence. The analysis revealed notable differences in pollen composition across the three bioclimatic zones, each exhibiting a distinct vegetation profile. Dominant tree and understory species varied between the regions. The PCA results demonstrated strong correlations between pollen assemblages, climatic gradients, and human impacts on vegetation distribution and structure. These findings underscore the reliability of pollen rain analysis as a valuable tool for monitoring plant biodiversity. By integrating climatic and environmental factors, the study highlights the effectiveness of airborne pollen analysis in enhancing our understanding of plant distribution, ecosystem dynamics, and the impacts of environmental change on biodiversity.